Fiiirrrrsssst to second-harsh shift

Hy everyone! New to the board. Have been reading posts for a long time and learning from various posts that have been helpful to me. Have a problem that I haven't seen addressed, so any info would be appreciated.

I had taken my K&N FIPK tube off my truck (89 350 tbi) because it cracked in a few different places. K&N was great about replacing the tube and even sent a check to reimburse me for the shipping. I had driven it for a long time with the FIPK being the only thing being changed. I installed the Airaid TBS at the same time I reinstalled the FIKP. I have read a lot of the opinions from individuals about whether it improves torque and HP. Don't know how much, but I do know that their is a significant increase in performance by having both. Not ready to race anyone, but it did help!

My problem after doing that is the truck will rev in first and will not shift to second even when you let off the accelerator. When you do speed up it will shift harshly even with moderate acceleration. My friend and I thought over time the computer would make an adjustment. After installing those two items I have driven it on a 300 mile trip and still have the same problem.

Any help or suggestions would be greatly appreciated.

Thanks!

If you have a TH350 or 400 trans. you might want to check to make sure you did not knock off the vacume line that goes from the back of the intake to the trans.

Thanks! I think my transmission is the 700r and it has a throttle valve (TV) cable. I still don't know what the problem is. I did read that certain codes doesn't automatically cause the service engine soon light to come on. A lot of people on here probably already knew that. I know that I will be checking mine more often now. I had one for the oxygen sensor and replaced it. Seems like it runs a little better after doing that. Still can't get out of first without a harsh shift unless going down hill. Still not sure if the K&N and TBI spacer has changed something, or I have done something that would effect the shifting.

Thanks! I think my transmission is the 700r and it has a throttle valve (TV) cable. I still don't know what the problem is. I did read that certain codes doesn't automatically cause the service engine soon light to come on. A lot of people on here probably already knew that. I know that I will be checking mine more often now. I had one for the oxygen sensor and replaced it. Seems like it runs a little better after doing that. Still can't get out of first without a harsh shift unless going down hill. Still not sure if the K&N and TBI spacer has changed something, or I have done something that would effect the shifting.


One other thing that I left out and not sure if it could be part of the problem. A few times my speedometer has quit. Haven't noticed it start working again while going down the road, but after you park the truck for a while it will start working again.

Any thoughts on that would be appreciated too.

The speedo not working is probably not related. Have you readjusted the TV cable? Here are instructions to do this http://tciauto.com/instructions/gm_tv_cable_adjust.htm

//2000CAYukon

The speedo not working is probably not related. Have you readjusted the TV cable? Here are instructions to do this http://tciauto.com/instructions/gm_tv_cable_adjust.htm

//2000CAYukon


That was the problem. Thank you so much! My Haynes manual had the written instructions, but I didn't know or understand where the adjustment tab was (I am not a mechanic for sure). The link you posted had pictures and good instructions.

Thanks again!

change your tranny fluid and filter. you might surprise yourself. a major percentage of tranny probs (mainly automatics) are attributed to bad fluid and filter.